


under pressure

by poisonpeaches



Series: uta no piss-sama [2]
Category: Uta no Prince-sama
Genre: Desperation, Dom/sub Undertones, Established Relationship, Humiliation, Light Sadism, M/M, Omorashi, Urination, Wetting, Whump
Language: English
Status: Completed
Published: 2020-08-14
Updated: 2020-08-14
Packaged: 2021-03-05 20:08:19
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,120
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/25891093
Author URL: https://archiveofourown.org/users/poisonpeaches/pseuds/poisonpeaches
Summary: Yamato and Kira's date goes awry when Yamato realizes he has a certain need that needs to be taken care of - and that he consistently ignores. Will he be able to hold off on it for long enough? Will he eventually give in? Or will Kira be the one to make him crack?
Relationships: Hyuuga Yamato/Sumeragi Kira
Series: uta no piss-sama [2]
Series URL: https://archiveofourown.org/series/1878589
Kudos: 11





	under pressure

**Author's Note:**

> kira is a fucking sadist lmao  
> warning: no sexual activity takes place in this fic, however it is fetish-centric, so tread with care!

How could a day that started off so lovely turn into something so disastrous?

Yamato and Kira were lucky enough to experience the rare phenomena of having a day off on the same day, so of course they chose to spend it with each other, and what better opportunity was there than this one to go on a date? Yamato surprised Kira by taking him to a rabbit cafe that had just opened recently. It was pretty far away from where they lived, about a forty-five minute drive, but they had the whole day to get over there, and Yamato really wanted to surprise his boyfriend. The wait time was huge, but Yamato was able to get them in hurriedly by lowering his face mask and lifting his sunglasses to reveal his identity to the host. He normally didn’t like making a big deal of the fact that he was an idol when he was out in public, but drastic times called for drastic measures, and Kira was adamantly against the use of their status to manipulate others, although any plans he had of scolding Yamato completely dissipated once he was sipping a matcha latte while surrounded by bunnies.

They should have just gone home right after the cafe. But Yamato had already made the drive out there, and it’s not like it was a quick one, so why not walk around downtown for a bit, he figured? It wasn’t until at least an hour later that a twinge of discomfort started to nip at Yamato. His grip around Kira’s arm clenched when he took note of the stinging sensation that was starting to brew in his lower abdomen, making the shorter man lift his head to peek at his boyfriend.

“Is… something… the matter?” Kira asked, his cool voice laced with concern.

“Mm…” His fingers curled even tighter around the pale flesh of Kira’s upper arm, careful not to dig his nails in. He knew that Kira had a bladder much smaller than his, and he had drank just as much liquid as Yamato did that day, but he hadn’t shown any signs of needing to relieve himself yet. For the sake of his pride, Yamato would stick it out a little longer. He took a deep breath, puffing up his chest and adopting a poker face. “I’m fine, Kira. Don’t worry. Let’s go check out that music shop that’s a few blocks from here.”

As they headed towards the shop, Kira noticed that Yamato’s footsteps seemed to be significantly heavier than usual. He was practically stomping his feet into the ground as they proceeded onwards, and he was pressing his lips together into a tight, thin line as if to stop any noises from leaking out, although a few little grunts and squeaks of unease managed to sound from his throat. Yamato really did not look alright, but he did tell Kira not to worry, and the raven-haired man didn’t want to annoy him if there truly was nothing wrong.

The music shop wasn’t all that interesting - not to Yamato, at least, since he was never really a musical person and didn’t care about it all that much outside of work-related stuff - but Kira seemed to be into it. As Kira leafed through a stack of records by some classical jazz musician that he liked, Yamato began to zone out, his amber eyes zeroing in on a laminated sign that hung right beneath the cash register at the front of the shop. _PUBLIC RESTROOM AVAILABLE TO ALL_ , it proudly declared. _EVEN NON-CUSTOMERS!_

The offer was so tempting, but Kira still hadn’t requested a restroom break, and Yamato didn’t want to go if Kira wasn’t also going to. The pressure around his pelvic bone suddenly felt like it was growing. Yamato kicked at the floor with his shoe to distract himself from the burning sensation building up inside of him. He was only brought back to the present when he noticed Kira was no longer standing next to him. His eyes darted around frantically until they settled on the form of his boyfriend, who was currently sauntering towards him.

“Where’d you run off to?” Yamato asked, arching an eyebrow.

“I had… to use… the restroom,” Kira explained. “You seemed… zoned out. So I just… went… without telling you.”

“Ah. Okay.”

Kira plucked a few records from the pile, smoothing his hand over their glossy sleeves. “I think… I’m going… to buy these. I’ll go… pay for them.”

 _Perfect._ Yamato could just slip off while Kira was occupied at the register. But would he be long enough for Yamato to just leave and go completely unnoticed? How long did it take for some items to be scanned and paid for? Kira was only getting two or three things, so it wasn’t like the cashier was going to spend a long time standing there ringing him up, and Kira was using his credit card in lieu of cash so there wouldn’t be the trouble of counting up the total and giving him his change either.

Yamato’s gaze began to narrowly focus on the door to the restroom, the rest of the world becoming blurred at the edges around him. The little silhouettes on the sign almost seemed to taunt him as he stared at them. His body suddenly felt heavier, and he could feel the liquid inside of him rising up and slapping against the inner walls of his system. He let out a groan of agony, then quickly covered it up by coughing, hoping it went unnoticed by the people around him. Was Kira still caught up in paying for the records? Did Yamato have time? He was brought out from his thoughts by a gentle hand landing against his shoulder and shaking him.

“Yamato.”

“Huh?” Yamato blinked, his gaze flitting down to look at his boyfriend.

Kira lifted a plastic bag that contained each of the records he’d just finished buying, along with his receipt. “I’m done. We… can go.”

“Oh.” Yamato cleared his throat. “Right.”

Kira blinked quizzically when he realized that Yamato’s gaze appeared to be fixed on something behind them. “Is there something… in the store… that you still wanted to look at?”

“Nope!” The single word sounded like it had been squeezed from Yamato’s throat as he tried to mask his discomfort with clearly forced cheerfulness. “I’m fine. Let’s move on!”

Kira’s brows knitted together into an expression of skepticism, but he saw it fruitless to argue. “… Right.”

They continued their date, strolling along the streets of downtown hand-in-hand with each other. Every few minutes, Yamato would give Kira’s hand a tight squeeze or stop abruptly before he kept walking. Kira would look at him with worry in his eyes each time, but Yamato would only look away, a bright red blush dusting his cheeks. Kira sighed. _Something_ was bothering Yamato, he knew that much was true. But he _also_ knew Yamato would never tell him. Why did he have to be so stubborn all the time? Kira loved him, but it could be frustrating when he got like this.

They eventually made their final pit stop in the center of a park, and it was by far the worst part of the whole day so far. Yamato’s eyes widened in horror, pupils shrinking into amber irises as Kira pulled him to a stop directly in front of a huge fountain. The pressure in Yamato’s lower abdomen seemed to stretch down to his thighs as he gazed upon the massive structure. Large streams of water gushed out from the valve in the center before raining down upon the clear, glittering water that pooled in the basin below.

The sound of the water rushing was all that occupied Yamato’s thoughts as his ears seemed to block out every other noise around him. It was getting hard to think. An even stronger heat bloomed from between his thighs and Yamato fought the urge to cross his legs and squeeze them together to kill the sensation. His muscles were starting to tingle, the static-like feeling spreading all the way into the tips of his fingers and toes. He fantasized about zipping down the fly of his pants and just releasing himself right into the fountain - if he was in a more private area, and without his boyfriend watching, he would have gone in for the kill. But he wasn’t about to start a media scandal and ruin his career and relationship just because he needed to piss, tempting as it may sound.

Beads of sweat began to materialize on Yamato’s forehead and roll down his temples. Kira was growing more concerned by the second, placing a hand on the small of Yamato’s back.

“Yamato,” he spoke gravely. “Are you _sure_ you’re alright?”

Yamato’s lips parted as the two sets of yellow eyes met. He wanted to voice his plight, but he couldn’t. No way was he going to let that happen. Shutting his mouth and nodding solemnly, he offered his boyfriend a lopsided smile that didn’t quite reach his eyes, which gained him a dubious look from the pianist. “Never better, babe.”

“… Alright.” Kira looked towards the sky, then back at Yamato. “Do you want… to leave now? It’s getting… dark out.”

Sure enough, the sun was beginning to set, shades of purple and orange bleeding into what was once a vibrant blue sky. Yamato frowned as he weighed his options - swallow his pride and try to find a restroom now, or try to hold out for the next forty-five or so minutes as they drove home. He toyed with the straps of his bag until he reached his decision.

_I can wait until we get home._

“Yeah. Let’s go.”

Smiling softly, Kira spun on his heel and started to head towards the park exit. Yamato took a step forward, which didn’t do much to quell the aching in his pelvis - it did quite the opposite, actually. He whimpered a bit, then cleared his throat. “Wait, actually… Kira?”

The raven-haired man turned around to face him. “Hm?”

 _Just tell him you need to use the bathroom before you leave and ask if you can look for a public one,_ Yamato willed himself. _Just fucking say it! Spit it out. It shouldn’t be that hard._ Smiling crookedly, he shook his head. “Never mind. It’s nothing. Let’s just go.”

Kira quirked an eyebrow in doubt. “… Okay…”

The walk back to their car took probably about five minutes, but to Yamato, it felt like a lifetime. He tried to distract himself with _anything_ \- admiring the colors of the sunset, counting how many dogs they passed by, keeping an eye out for any HE★VENS posters plastered onto buildings, but it was no use. He couldn’t seem to think of anything else but the mounting tension in his crotch. A voice in the back of his head instructed him to turn around and go back, to find the nearest restroom and empty the contents of his bladder until there was nothing left, but he firmly told that voice to shut up. It could wait. He didn’t have a choice at this point.

The two got into the car, Yamato assuming his usual position behind the wheel, and pulled out of the parking lot. Driving thankfully gave Yamato something to focus his attention on other than the strain in his bladder. Unfortunately, though, it also meant he had to relinquish his ability to fidget freely. Kira would definitely notice something was up if Yamato squirmed in his seat too much, so the blonde tried his damnedest to keep himself still and focus solely on the road ahead. He would catch himself bouncing his knee or tapping his fingers against the steering wheel every once in a while, but quickly stopped himself before Kira was able to point it out.

Before long, the two men were back on the highway. A horrific realization dawned over Yamato as he saw the miles of barely-moving cars spanning out in front of them - they forgot to take into account the evening traffic. Yamato moaned, slamming his forehead against the wheel as he slowed to a stop behind a Honda Civic. “Fuck, fuck, fuck, no…”

The GPS on his phone cheerfully alerted them that the estimated time in traffic was an hour, and Yamato’s knuckles turned white as he gripped the wheel. “Shut up, stupid bitch!” he roared at the phone, not flinching when Kira placed a hand against his shoulder comfortingly.

“Yamato… it’s fine,” he whispered.

Yamato almost wanted to sob at the feeling of Kira touching and speaking to him so soothingly, but he choked it back. He couldn’t give off the impression that everything wasn’t fine. But it was so fucking hard with how much pain he was in right now. He couldn’t even muster a smile of relief as the car in front of them began to roll forward. An hour in traffic, plus the forty-five minutes it would already take them to get home, meant almost two hours of Yamato having to will himself not to fucking _explode_. This was going to be a long night.

Maybe he had died at some point earlier in the day, and this was his own personal hell.

By the time they hit the hour and fifteen minute mark, Kira had fallen asleep in his seat, tired from a full day of walking around. Any other time, Yamato would have been admiring how peaceful and cute Kira looked when he was asleep, but he couldn’t concentrate on anything other than his need to use the bathroom. Thankfully, Kira taking an impromptu nap gave Yamato the freedom to shift and squirm as much as he pleased without his boyfriend noticing. The car ahead of them lurched forward another ten feet or so, then halted. “Son of a bitch,” Yamato muttered under his breath, closing the distance between them.

He clumsily unbuckled his seatbelt. The car wasn’t moving, and all it did was add more pressure onto his bladder than he needed to be feeling right now. Unsurprisingly, it didn’t do much.

The traffic began to move once again, and not just a little bit at a time - it was still slower than Yamato would have liked, but a vast improvement from the sluggishness of earlier. He begrudgingly put his seatbelt back on, which only made his predicament worse, but he had to prioritize his safety, or whatever.

His eyes quickly tore away from the road to briefly glance at the GPS - a mere twenty minutes until they were home. Yamato wanted to tear up when the freeway exit finally entered into his line of vision. “Thank you,” he mouthed to no one in particular. “Thank you, _thank_ you, _fuck_.”

Perhaps he spoke too soon, because just then, a short spurt of liquid dampened his boxers. The feeling of panic coursing through him was unmatched by any sort of physical malaise he had experienced throughout the day. “ _Shit_ ,” he hissed, pressing his knees together as he leaned forward in his seat. Only half paying attention to the road by this point, he quickly looked at his crotch and removed one hand from the steering wheel to feel the spot beneath him - he let out a breath of relief he hadn’t realized he’d been holding when he felt that the leather underneath him was completely dry, turning his attention back to the GPS. Just fifteen more minutes. All he needed to do was hold on for fifteen more minutes.

“Yamato?”

The blood drained from the blonde’s face as he heard his boyfriend’s thick, sleep-heavy voice from beside him. Trying not to show any visible signs of discomfort on his face, he forced a grin, but Kira wasn’t buying it. “Fifteen minutes, baby. We’ll be home in just fifteen more minutes.” He said it to himself more so than to Kira, really.

The uncomfortable cramping from an hour ago felt like little more than a light tickle compared to the suffering Yamato was enduring right now. His bladder was contracting and twisting with every little move he made; even the slightest twitch of his fingers would send streaks of pain directly down to his groin. He silently thanked whatever Gods there were when Kira rolled back over and returned to slumber, allowing him to continue wiggling in his seat like a fish removed from water. Yamato was now hyper-aware of every second that passed, every little inch the car moved that brought them closer to their destination, closer to Yamato’s sweet release.

All the lights in the windows were off as Yamato pulled up in front of the house they shared with the other five members of HE★VENS, suggesting that everyone else was either out or had gone to bed already. Thank _God_ , because Yamato was already humiliated just at the prospect of allowing Kira to see him in this state; he didn’t think he could handle it if the others saw him as well.

“We’re home,” he whispered gruffly, shaking Kira’s shoulder gently until those golden eyes fluttered open to meet his. He didn’t want to wake Kira up, but it was all he could do not to just give in to nature’s call right then and there. He flung the door open and yanked his seatbelt off, not even caring if he was making a scene or not anymore. He needed to get out of this fucking car and into the house as _fast_ as he could.

Yamato inhaled sharply at the sudden wave of desperation that pulsed through him as he stood up. He waited impatiently for his boyfriend to get out of the car, locking it and marching off towards the house as soon as he heard the soft thud of Kira’s car door shutting behind him. Whether or not Kira knew what was going on was completely unconcerning to him by this point. Getting to the bathroom was the only thing on his mind right now.

Yamato pushed his hands into his bag, fingers fumbling around blindly for his keys. It was too dark, and he couldn’t see, and his keys must have been buried deep under all the other shit he had in there because he was _not_ finding them. _Fuck._

The athlete futilely crossed one leg over the other to subside the unpleasant buildup in his nether regions as he continued his frantic search for his keys. He let out a sigh of relief when his fingers latched around something metal, but as he whipped the key out from his bag, he was abruptly interrupted by a pale hand coming around his.

Yamato opened his mouth to say something, but couldn’t get so much as a letter out before Kira’s soft lips attached themselves to his. His lips were soft, sweet, heavenly. Everything Kira was. Yamato wanted to remain locked in that angelic embrace for so much longer, but his body was beginning to lose its patience, which he made clear by shoving Kira off of him. “Kira, I - ”

He started to say something, but Kira only cut him off with another kiss, this one slightly more intense than the last. He reluctantly withdrew from the kiss once more as he felt his control slipping further and further away from him with each second that passed. “I… I can’t do this right now,” he hissed.

Kira blinked at him. “Why not?” he asked innocently, snaking his arms around the taller man’s waist.

The blonde’s knees buckled, his muscles beginning to tremble under him. “I need to pee,” he admittedly weakly, his voice coming out small in a hushed whisper.

Kira took a step closer to Yamato, leaving one arm strewn around his waist while another crept up his back, finally coming to rest at the nape of his neck. The pianist tilted his head up to slide his lips along the sharp curve of Yamato’s jawline, nipping at the flush skin playfully. “Are you sure… you can’t wait… a little longer?” he purred, his hot breath making Yamato break out in goosebumps.

It was unbelievably alluring, this side of Kira, but Yamato’s muscles were screaming for release, his mind ticking away the seconds he had left until he lost this battle with his body. He shook his head vigorously. “I’m serious, Kira, I _really_ need to go.” It came out in the form of a desperate whimper, but it didn’t even matter anymore. All concerns of maintaining his manliness completely left Yamato’s mind as he practically begged. Nothing was important right now aside from getting to a bathroom _immediately_.

Yamato waited from Kira to untangle himself from their embrace, but he never did. “Why not… just go right here… then?”

“What?” Yamato jolted back, glaring at his boyfriend with wide eyes. He wanted to believe Kira was kidding - for fuck’s sake, Yamato had been holding his piss for nearly _five hours_ by this point! - but Kira wasn’t the type of person to make jokes. Another quick spurt dampened Yamato’s underwear, longer than the last one, and he gritted his teeth in desperation.

“I said… just go… right here.” Yamato didn’t miss the tiny smile pulling at the corners of Kira’s soft lips, nor the sparkle swimming in his lemon irises, or the rosy hue creeping across his porcelain cheeks.

_Wait… is he fucking turned on by this shit?_

There was no mistaking the familiar gaze gracing his boyfriend’s features. Yamato didn’t want to do this. He really didn’t want to. But it didn’t look like Kira was planning to let him go inside any time soon, and if he didn’t give in soon, his body was going to do so for him. Shrinking under Kira’s lustful glare, Yamato tentatively uncrossed his legs, allowed his muscles to relax, and, finally, for the first time in what felt like an eternity, let himself answer nature’s call.

It started as just a few droplets that leaked from the head of his panging cock, before they eventually began to pour out in long, heavy streams, soaking both the crotch of his pants and the ground beneath him. A loud sibilation filled the air as his sore, miserable bladder purged itself of all its contents. Kira kept a firm grip on Yamato’s forearms to keep him stable as the taller man succumbed to his needs, not letting his eyes divert from Yamato’s face for a second so he could hungrily drink in every tiny change in the athlete’s expression.

As for Yamato, the feeling of release was so euphoric that he felt as if he had entered another plane of existence; it was almost worth all those traumatic, agony-filled hours. His knees buckled, his vision went fuzzy around the edges, and he couldn’t stop himself from letting out a satisfied cry of pleasure.

Finally, Yamato’s gratified moan dulled into light panting and the stream between his legs tapered off into nothing. His mind was buzzing with so much ecstasy that he almost forgot Kira was in front of him until the smaller man wrapped his arms around him, leaning his head against him so he could hear and feel every thump that rang out in the blonde’s strong chest. “…Good boy.” A shiver billowed up Yamato's spine when he felt the smoke of Kira's voice fluttering again his chest, even more so at the words he was saying.

“You did… really well. I’m very… proud of you… for holding out this long.”

So Kira _did_ know the whole time. Yamato said nothing, only rested his head on top of his boyfriend’s as his breathing slowly began to return to a normal rate.

“You’re… very beautiful… like this… Yamato,” the black-haired man spoke, the sentence strung together carefully as if it was a conclusion he had done a lot of mental math to arrive at.

“What, you mean soaked in my own piss?” Yamato asked, a bite behind his words that was more the product of confusion than anger.

Without answering him, Kira snatched the keys from Yamato’s hands and slid them into the lock on the door before wordlessly ambling off into the house.

The blonde stared until the slender form of his boyfriend disappeared into the darkness of the unlit hallway. He shifted his attention back to the puddle he had created on the ground, trying to ignore the feeling of dampness that spanned out across the crotch of his pants. He would definitely have to wash those later, but…

“At least he made me go outside,” Yamato muttered before heading inside and closing the door behind him. No way did he want to spend the rest of his night mopping up piss stains on the floor.


End file.
